The first total synthesis of marine sesquiterpene(hydro)quinone meroterpenoids dysideanones A and E–G(1 and 4–6)has been accomplished in an enantioselective and divergent way.The sesquiterpene fragment and the aroma...The first total synthesis of marine sesquiterpene(hydro)quinone meroterpenoids dysideanones A and E–G(1 and 4–6)has been accomplished in an enantioselective and divergent way.The sesquiterpene fragment and the aromatic moiety were efficiently connected via a site-selective and diastereoselective intermolecular alkylation of Wieland–Miescher ketone derivative 9 and benzyl bromide 10.The core 6/6/6/6-fused backbone of dysideanones was efficiently constructed through an intramolecular radical cyclization reaction.Dysideanone G(6)was easily prepared on a gram-scale and dysideanones A,E,and F(1,4,and 5)were divergently transformed from dysideanone G(6)in one or two steps.展开更多
Pyrroloquinoline quinone is a quinone described as a cofactor for many bacterial dehydrogenases and is reported to exert an effect on metabolism in mammalian cells/tissues.Pyrroloquinoline quinone is present in the di...Pyrroloquinoline quinone is a quinone described as a cofactor for many bacterial dehydrogenases and is reported to exert an effect on metabolism in mammalian cells/tissues.Pyrroloquinoline quinone is present in the diet being available in foodstuffs,conferring the potential of this compound to be supplemented by dietary administration.Pyrroloquinoline quinone’s nutritional role in mammalian health is supported by the extensive deficits in reproduction,growth,and immunity resulting from the dietary absence of pyrroloquinoline quinone,and as such,pyrroloquinoline quinone has been considered as a“new vitamin.”Although the classification of pyrroloquinoline quinone as a vitamin needs to be properly established,the wide range of benefits for health provided has been reported in many studies.In this respect,pyrroloquinoline quinone seems to be particularly involved in regulating cell signaling pathways that promote metabolic and mitochondrial processes in many experimental contexts,thus dictating the rationale to consider pyrroloquinoline quinone as a vital compound for mammalian life.Through the regulation of different metabolic mechanisms,pyrroloquinoline quinone may improve clinical deficits where dysfunctional metabolism and mitochondrial activity contribute to induce cell damage and death.Pyrroloquinoline quinone has been demonstrated to have neuroprotective properties in different experimental models of neurodegeneration,although the link between pyrroloquinoline quinone-promoted metabolism and improved neuronal viability in some of such contexts is still to be fully elucidated.Here,we review the general properties of pyrroloquinoline quinone and its capacity to modulate metabolic and mitochondrial mechanisms in physiological contexts.In addition,we analyze the neuroprotective properties of pyrroloquinoline quinone in different neurodegenerative conditions and consider future perspectives for pyrroloquinoline quinone’s potential in health and disease.展开更多
A novel coordination polymer [Ba2（AQTC）（H2O）3]n（1, H4 AQTC = anthraquinone-1,4,5,8-tetracarboxylic acid） has been prepared under hydrothermal conditions and characterized by single-crystal X-ray diffraction, ele...A novel coordination polymer [Ba2（AQTC）（H2O）3]n（1, H4 AQTC = anthraquinone-1,4,5,8-tetracarboxylic acid） has been prepared under hydrothermal conditions and characterized by single-crystal X-ray diffraction, elemental analysis, infrared spectroscopy and thermogravimetric analysis. Two quinone oxygen atoms and all carboxylate oxygen atoms of AQTC4- are involved in coordination. Two equivalent barium ions are mainly linked by carboxylate oxygen atoms into a dimer. Neighbouring dimers are further connected by the AQTC4- ligand through carboxylate oxygen atom, leading to a 1-D chain structure. Every two adjacent chains are mainly further connected by face carboxylate oxygen atoms and water molecule, generating a two-dimensional layer structure. Such 2-D layer structures are connected with O（6） and O（6C） atoms from water molecules to form a 3-D structure. In addition, luminescent properties of 1 are also investigated.展开更多
Background: Pyrroloquinoline quinone(PQQ), which is a water soluble, thermo-stable triglyceride-quinone, is widely distributed in nature and characterized as a mammalian vitamin-like redox cofactor. The objective of t...Background: Pyrroloquinoline quinone(PQQ), which is a water soluble, thermo-stable triglyceride-quinone, is widely distributed in nature and characterized as a mammalian vitamin-like redox cofactor. The objective of this study was to investigate the effects of pyrroloquinoline quinone disodium(PQQ·Na2) on reproductive performance in sows.Results: Dietary supplementation with PQQ·Na2 significantly increased the total number of piglets born, the number of piglets born alive and the born alive litter weight. It also increased the antioxidant status in the placenta, plasma and milk. The concentration of NO was significantly increased in the plasma and placenta. RNA-seq analysis showed that462 unigenes were differentially expressed between the control(Con) treatment and PQQ treatment groups.Among these unigenes, 199 were upregulated, while 263 unigenes were downregulated. The assigned functions of the unigenes covered a broad range of GO categories. Reproduction(27, 7.03%) and the reproduction process(27, 7.03%) were assigned to the biological process category. By matching DEGs to the KEGG database, we identified 29 pathways.Conclusions: In conclusion, dietary supplementation with PQQ·Na2 in gestating and lactating sows had positive effects on their reproductive performance.展开更多
Background:Oxidative stress is a main cause of piglet gut damage and diarrhea.Pyrroloquinoline quinone(PQQ),is a novel redox cofactor with antioxidant properties.However,the effect and mechanism that PQQ supplementati...Background:Oxidative stress is a main cause of piglet gut damage and diarrhea.Pyrroloquinoline quinone(PQQ),is a novel redox cofactor with antioxidant properties.However,the effect and mechanism that PQQ supplementation decreases oxidative injury in weaned pigs is not understood.Therefore,the aim of this study is to confirm the effect of PQQ on regulating redox status in weaned pigs and the mechanism for antioxidant function by porcine intestinal epithelial cell line(IPEC-J2)challenged with H_(2)O_(2).Results:Experiment 1,144 Duroc×Landrace×Yorkshire pigs(weaned at 28 d)were allocated to four groups:received a basal diet(control)and diets supplemented with 0.15%,0.30%and 0.45%PQQ,respectively.On d 28,growth performance,diarrhea incidence and redox factors were measured.Experiment 2,IPEC-J2 were treated with or without PQQ in the presence or absence of H_(2)O_(2)for indicated time points.Experiment 3,IPEC-J2 were transfected with or without Nrf2 siRNA,then treated according to Experiment 2.The cell viability,redox factors,protein of tight junctions and Nrf2 pathway were determined.In vivo,PQQ supplementation demonstrated dose-related improvements in average daily gain,and gain to feed ratio(Linear P<0.05).During d 0–28,compared to controls,0.45%PQQ supplementation for pigs decreased diarrhea incidence and MDA content in liver and jejunum,and increased concentration of SOD in liver;0.3%PQQ supplementation decreased ileal and liver MDA concentration;and 0.15%PQQ supplementation decreased ileal MDA concentration(P<0.05).In vitro,compared to cells cultured with H_(2)O_(2),pre-treatment with PQQ increased cell viability,tight junction proteins expression including ZO-1,ZO-2,Occludin and Claudin-1;and decreased ROS concentration and level of Caspase-3(P<0.05);as well as upregulated the ratio of Bcl-2 to Bax and protein expression of nuclear Nrf2,HO-1.Notably,Nrf2 knockdown by transfection with Nrf2 siRNA largely abrogated the positive effects of PQQ pretreatment on H_(2)O_(2)-induced intracellular changes.Conclusions:PQQ administration attenuated oxidative stress in weaned pigs which is associated with activation of Nrf2/HO-1 pathway.展开更多
Two new diterpenoid quinones, colean S and T were isolated from the chloroform extract of the leaves of Coleus forskohlii, and based on spectroscopic data, their structures were identified as 1,4-phananthrenedione-4b,...Two new diterpenoid quinones, colean S and T were isolated from the chloroform extract of the leaves of Coleus forskohlii, and based on spectroscopic data, their structures were identified as 1,4-phananthrenedione-4b,5,6,8a,9,10-hexahydro-3,9 beta ,10 alpha- tri-hydroxy-4b,7,8-trimethyl-2-propylene(2), respectively.展开更多
Osteoarthritis(OA)is a degenerative disease characterized by matrix degradation and cell death leading to a gradual loss of articular cartilage integrity.As a bacterial synthesis of quinine,pyrroloquinoline quinone(PQ...Osteoarthritis(OA)is a degenerative disease characterized by matrix degradation and cell death leading to a gradual loss of articular cartilage integrity.As a bacterial synthesis of quinine,pyrroloquinoline quinone(PQQ)is a strong redox cofactor with a variety of biological benefits,including antioxidant,anti-inflammation-induced mitochondrial metabolism regulation.This study was designed to investigate the effect of PQQ on TNF-α-induced mitochondrial damage in chondrocytes.Chondrocytes isolated from C57BL/6 mice were exposed to TNF-α50 ng/mL,TNF-α50 ng/mL+PQQ 10µmol/L for 24 h.Then,morphological study,functional study and mechanism study were taken.The results revealed TNF-α-induced chondrocyte mitochondrion damage could be reduced by application of PQQ,evidenced by elevated number of mitochondria,well-kept mtDNA integrity,preserved ATP level,reestablished mitochondrial membrane potential,and prevented mitochondrial function.The present work strongly suggests that the mitochondrion is an important target for OA chondrocyte damage induced by TNF-αand the PQQ protection from this damage ameliorates mitochondrial dysfunction induced by TNF-α.PQQ might be a potential chemical for OA intervention.展开更多
BACKGROUND Quinine oxidoreductase 1(NQO1)plays a vital role in protecting normal cells against oxidative damage and electrophilic attack.It is highly expressed in many solid tumors,suggesting a role in cancer developm...BACKGROUND Quinine oxidoreductase 1(NQO1)plays a vital role in protecting normal cells against oxidative damage and electrophilic attack.It is highly expressed in many solid tumors,suggesting a role in cancer development and progression.However,the role of NQO1 in gastric cancer and its effect on cancer development and prognosis have not been fully investigated.AIM To investigate the clinical relevance of NQO1 protein expression in gastric cancer and to explore the potential of NQO1 to serve as a prognostic biomarker and therapeutic target.METHODS In this retrospective study,gastric cancer specimens of 175 patients who were treated between 1995 and 2011 were subjected to immunohistochemistry analyses for NQO1.The correlation of NQO1 expression with gastric cancer prognosis and clinical and pathological parameters was investigated.RESULTS NQO1 protein was overexpressed in 59.43%(104/175)of the analyzed samples.Overexpression of NQO1 was associated with a significantly inferior prognosis.In addition,multivariate analysis suggested that NQO1 overexpression,along with tumor stage and patient age,are prominent prognostic biomarkers for gastric cancer.Moreover,NQO1 overexpression was correlated to a better response to 5-fluorouracil(5-FU)-based adjuvant chemotherapy.CONCLUSION NQO1 overexpression is associated with a significantly poor prognosis and better response to 5-FU in patients with gastric cancer.These findings are relevant for improving therapeutic approaches for gastric cancer patients.展开更多
This study was conducted to investigate the effect of dietary supplementation with pyrroloquinoline quinone(PQQ) in the form of PQQ disodium(PQQ·Na2) on the growth performance, carcass traits, meat quality and an...This study was conducted to investigate the effect of dietary supplementation with pyrroloquinoline quinone(PQQ) in the form of PQQ disodium(PQQ·Na2) on the growth performance, carcass traits, meat quality and antioxidative ability of broilers. A total of 720 one-d-old Arbor Acres male broilers were randomly allocated to 1 of 6 treatments with 8 replicates of 15 birds per replicate in a completely randomized design. Birds were fed a PQQ·Na2-unsupplemented corn-soybean meal basal diet(control) or the basal diet supplemented with 0.1, 0.2, 0.3, 0.4 or 0.5 mg PQQ·Na2 kg-1 for 42 d. Compared with the control chicks, the chicks fed the diets supplemented with PQQ·Na2 had lower(P<0.05) feed:gain(F/G) during the grower phase and drip losses of breast muscles on day 42. As supplemental PQQ·Na2 level increased, plasma total antioxidant capacity(T-AOC) on d 42, liver T-AOC on d 21 and heart T-AOC on d 21 and 42 increased linearly(P<0.05), but malondialdehyde concentrations in plasma, liver and heart on d 21 or 42 decreased linearly(P<0.001) or quadratically(P<0.005). The results from the present study indicate that dietary supplemental PQQ·Na2 can improve antioxidant ability and meat quality of broilers, and in general, it is implied that the optimal supplemental PQQ·Na2 level is 0.1 mg kg-1 of diet for broilers from 1 to 42 d of age.展开更多
AIM： To investigate the expression and activity of NAD（P）H quinone oxidoreductase 1 （NQO1） in human liver specimens obtained from patients with liver damage due to acetaminophen （APAP） overdose or primary bilia...AIM： To investigate the expression and activity of NAD（P）H quinone oxidoreductase 1 （NQO1） in human liver specimens obtained from patients with liver damage due to acetaminophen （APAP） overdose or primary biliary cirrhosis （PBC）. METHODS： NQOt activity was determined in cytosol from normal, APAP and PBC liver specimens. Western blot and immunohistochemical staining were used to determine patterns of NQO1 expression using a specific antibody against NQO1. RESULTS： NQO1 protein was very low in normal human livers. In both APAP and PBC livers, there was strong induction of NQO1 protein levels on Western blot. Correspondingly, significant up-regulation of enzyme activity （16- and 22-fold, P〈0.05） was also observed in APAP and PBC livers, respectively. Immunohistochemical analysis highlighted injury-specific patterns of NQO1 staining in both APAP and PBC livers. CONCLUSION： These data demonstrate that NQO1 protein and activity are markedly induced in human livers during both APAP overdose and PBC. Up-regulation of this cytoprotective enzyme may represent an adaptive stress response to limit further disease progression by detoxifying reactive species.展开更多
Four new sesquiterpene quinone meroterpenoids,dysideanones F—G(1—2)and dysiherbols D—E(3—4),were isolated from the marine sponge Dysidea avara collected from the South China Sea.The new structures were elucidated ...Four new sesquiterpene quinone meroterpenoids,dysideanones F—G(1—2)and dysiherbols D—E(3—4),were isolated from the marine sponge Dysidea avara collected from the South China Sea.The new structures were elucidated by extensive analysis of spectroscopic data including HR-MS and 1D and 2D NMR spectra,and their absolute configurations were assigned by single-crystal X-ray diffraction and ECD calculations.Anti-inflammatory evaluation showed that dysiherbols D—E(3—4)exhibited moderate inhibitory activity on TNF-α-induced NF-κB activation in human HEK-293T cells with IC_(50)values of 10.2 and 8.6μmol·L^(-1),respectively.展开更多
Our previous studies showed that resveratrol could inhibit the proliferation of vascular smooth muscle cells （VSMCs） and repress mRNA and protein expression of quinone reductase 2 （NQO2）. This study further explor...Our previous studies showed that resveratrol could inhibit the proliferation of vascular smooth muscle cells （VSMCs） and repress mRNA and protein expression of quinone reductase 2 （NQO2）. This study further explored the potential mechanisms whereby resveratrol inhibits the proliferation of rat VSMCs. Lentiviral vectors that incorporated NQO2 small interfering RNA （siRNA） were constructed and transduced into rat VSMCs. The cell proliferation was detected using the bromodeoxyuridine （BrdU） assay. Cultured rat VSMCs were stimulated with angiotensin II and the level of reactive oxygen species （ROS） was measured using a ROS assay kit. A realtime quantitative PCR was used to detect NQO2 mRNA levels. Extracellular signal-regulated kinase （ERK1/2） and NQO2 protein expression were determined by Western blotting analysis. The inhibitory effect of resveratrol （10 and 50 μmol/L） on the proliferation of rat VSMCs in the NQO2 siRNA group was significantly weaker than that in the normal and scrambled siRNA group （P 〈 0.01）. The ROS level in the NQO2 siRNA and resveratrol （50 μmol/L） treatment groups were lower than that in the normal and scrambled siRNA groups （P 〈 0.01 in both）. Compared with the normal and scrambled siRNA group, the phosphorylation of ERK1/2 was significantly decreased in the NQO2 siRNA and resveratrol （50 μmol/L） treatment group （P 〈 0.01 in both）. In conclusion, high concentration of resveratrol inhibits angiotensin II-induced ERK1/2 phosphorylation and subsequent proliferation by down-regulation of NQO2 in cultured rat VSMCs.展开更多
Objective:To validate scientifically the traditional use of Salacia leptoclada Tul.(Celastraceae)(S.leptoclada)and to isolate and elucidate the structure of the biologically active compound.Methods:Bioassay-guided fra...Objective:To validate scientifically the traditional use of Salacia leptoclada Tul.(Celastraceae)(S.leptoclada)and to isolate and elucidate the structure of the biologically active compound.Methods:Bioassay-guided fractionation of the acetonic extract of the stem barks of S.leptoclada was carried out by a combination of chromatography technique and biological experiments in viro using Plasmodium falciparum and P388 leukemia cell lines as models.The structure of the biologically active pure compound was elucidated by 1D and 2D NMR spectroscopy and mass spectrometry.Results:Biological screening of S.leptoclada extracts resulted in the isolation of a pentacyclic triterpenic quinone methide.The pure compound exhibited both in vitro a cytotoxic effect on murine P388 leukemia cells with IC_(50)value of(0.041±0.020)μg/mL and an antiplasmodial activity against the chloroquine-resistant strain FC29 of Plasmodium falciparum with an IC_(50)value of(0.052±0.030)μg/mL.Despite this interesting anti-malarial property of the lead compound,the therapeutic index was weak(0.788).In the best of our knowledge,the quinone methide pentacyclic triterpenoid derivative compound is reported for the first time in S.leptoclada.Conclusions:The results suggest that furthers studies involving antineoplastic activity is needed for the development of this lead compound as anticancer drug.展开更多
The structures of two new abietane quinones, named micranthins A and B, were determined to be 7a-methoxy-14, 16-epoxy-8, 13-abietadiene-11, 12-dione (1) and 16-acetoxy-6, 7-dehydroroyleanone (2) respectively, which we...The structures of two new abietane quinones, named micranthins A and B, were determined to be 7a-methoxy-14, 16-epoxy-8, 13-abietadiene-11, 12-dione (1) and 16-acetoxy-6, 7-dehydroroyleanone (2) respectively, which were isolated from Isodon lophanthoides var. micranthus.展开更多
CIDNP techniques were applied to study the mechanism of photocycloadditions of 2-chloro-5-methoxybenzoquinone 1 with arylacetylenes 2-5 in benzene-d6 and acetonitrile-d6 respectively.
Photocatalytic splitting of water was carried out in a two-phase system. Nanocrystalline titanium dioxide was used as photocatalyst and potassium hexacyanoferrate(III)/(II) as electron transporter. Generated hydrogen ...Photocatalytic splitting of water was carried out in a two-phase system. Nanocrystalline titanium dioxide was used as photocatalyst and potassium hexacyanoferrate(III)/(II) as electron transporter. Generated hydrogen was chemically stored by use of a 1,4-benzoquinone/1,4-hydroquinone system, which was used as a recyclable fuel in a commercialised direct methanol fuel cell (DMFC). The electrical output of the cell was about half compared to methanol. The conversion process for water splitting and recombination in a fuel cell was monitored by UV-Vis spectroscopy and compared to a simulated spectrum. Products of side reactions, which lead to a decrease of the overall efficiency, were identified based on UV-Vis investigations. A proof of principle for the use of quinoide systems as a recyclable hydrogen storage system in a photocatalytic water splitting and fuel cell cyclic process was given.展开更多
Resveratrol is a dietary polyphenol espoused to have chemopreventive activity against a variety of human cancer types. We first reported that resveratrol significantly decreases the proliferation of both androgen-depe...Resveratrol is a dietary polyphenol espoused to have chemopreventive activity against a variety of human cancer types. We first reported that resveratrol significantly decreases the proliferation of both androgen-dependent and hormone-refractory prostate cancer cells. However, the effects of resveratrol in normal prostate epithelial and stromal cells, particularly with regard to its uptake, subcellular distribution and intracellular targets, have not been investigated. To advance the knowledge on accessibility and cellular disposition of resveratrol in prostate cells, [3H] resveratrol, fractionation of cell extracts into subcellular compartments, Western blot analysis, resveratrol affinity column chromatography and flow cytometry were used to study the uptake and intracellular distribution of resveratrol in normally cultured prostate stromal （PrSCs） and epithelial cells （PrECs）. Pretreatment of both PrSCs and PrECs for 2 days with resveratrol modulated its uptake and selectively increased its distribution to the membrane and organelle compartments. Resveratrol affinity column chromatography studies showed differential expression of a previously identified resveratrol-targeting protein, quinone reductase 2 （QR2）, in PrSCs and PrECs. Flow cytometric analysis comparing resveratrol-treated and untreated PrSCs showed a large decrease in G1-phase and a concomitant increase in S and G2/M-phases of the cell cycle. These results suggest that resveratrol suppresses PrSC proliferation by affecting cell cycle phase distribution, which may involve the participation by QR2.展开更多
Emodin and shikonin are quinones that are commonly found in the roots of plant species of the families Polygonaceae and Boraginceae,respectively.They have a wide spectrum of bioactivities,including anti-cancer propert...Emodin and shikonin are quinones that are commonly found in the roots of plant species of the families Polygonaceae and Boraginceae,respectively.They have a wide spectrum of bioactivities,including anti-cancer properties.This overview on the cytotoxic properties of emodin and shikonin is focused on lung cancer,the leading cause of cancer death in the world.In emodin,the-OH groups at C1 and C3 positions,while in shikonin,the-OH groups of the naphthazarin moiety and chiral side-chain,are important for their anti-tumour functions.Studies have shown that emodin and shikonin inhibit the growth of lung cancer cells by inducing apoptosis,autophagy,necrosis and early senescence,and by inhibiting proliferation,invasion,migration and metastasis.The cytotoxic activities are involved multiple molecular targets and signalling pathways.A clinical trial using shikonin to treat patients with late-stage lung cancer has been presented.Some future perspectives and research needs are suggested.Sources of information are from Google Scholar,Pub Med,Science Direct,J-Stage,Pub Chem and CNKI.展开更多
Water-soluble pillar[5]arenes are a class of typical macrocycles and have aroused tremendous attention for its easy to modify, abundant host-vip properties and extensive applications. However, up to now, all the rep...Water-soluble pillar[5]arenes are a class of typical macrocycles and have aroused tremendous attention for its easy to modify, abundant host-vip properties and extensive applications. However, up to now, all the reported water-soluble pillar[5]arenes acted as the host molecules, whereas they failed to be postsynthetically modified, which seriously impeded the development of the pillar[5]arene-based supramolecular chemistry. In this work, a new water-soluble pillar[5]arene, pillar[4]arene[1]quinone, was designed and synthsized with eight quaternary ammonium groups as well as a quinone units. Such a new water-soluble pillar[4]arene[1]quinone was capable of forming 1:1 stable complex with sodium 1-octanesulfonate in aqueous solution. Since the 1,4-quinone unit of WP[4]Q[1] could react with ethylenediamine (EDA) to form a conjugated quinoxaline structure, so pillar[4]arene[1]quinone could apply to the facile fluorescence turn-on sensing of EDA in aqueous solution, organic solvent and air.展开更多
基金Financial support for this work was provided by the National Natural Science Foundation of China(Nos.22171146,21971121,and 22188101)the Fundamental Research Funds for the Central Universities,Nankai University(No.63231199)the State Key Laboratory of Medicinal Chemical Biology。
文摘The first total synthesis of marine sesquiterpene(hydro)quinone meroterpenoids dysideanones A and E–G(1 and 4–6)has been accomplished in an enantioselective and divergent way.The sesquiterpene fragment and the aromatic moiety were efficiently connected via a site-selective and diastereoselective intermolecular alkylation of Wieland–Miescher ketone derivative 9 and benzyl bromide 10.The core 6/6/6/6-fused backbone of dysideanones was efficiently constructed through an intramolecular radical cyclization reaction.Dysideanone G(6)was easily prepared on a gram-scale and dysideanones A,E,and F(1,4,and 5)were divergently transformed from dysideanone G(6)in one or two steps.
基金supported by Karolinska Institutet in the form of a Board of Research Faculty Funded Career Positionby St.Erik Eye Hospital philanthropic donationsVetenskapsrådet 2022-00799.
文摘Pyrroloquinoline quinone is a quinone described as a cofactor for many bacterial dehydrogenases and is reported to exert an effect on metabolism in mammalian cells/tissues.Pyrroloquinoline quinone is present in the diet being available in foodstuffs,conferring the potential of this compound to be supplemented by dietary administration.Pyrroloquinoline quinone’s nutritional role in mammalian health is supported by the extensive deficits in reproduction,growth,and immunity resulting from the dietary absence of pyrroloquinoline quinone,and as such,pyrroloquinoline quinone has been considered as a“new vitamin.”Although the classification of pyrroloquinoline quinone as a vitamin needs to be properly established,the wide range of benefits for health provided has been reported in many studies.In this respect,pyrroloquinoline quinone seems to be particularly involved in regulating cell signaling pathways that promote metabolic and mitochondrial processes in many experimental contexts,thus dictating the rationale to consider pyrroloquinoline quinone as a vital compound for mammalian life.Through the regulation of different metabolic mechanisms,pyrroloquinoline quinone may improve clinical deficits where dysfunctional metabolism and mitochondrial activity contribute to induce cell damage and death.Pyrroloquinoline quinone has been demonstrated to have neuroprotective properties in different experimental models of neurodegeneration,although the link between pyrroloquinoline quinone-promoted metabolism and improved neuronal viability in some of such contexts is still to be fully elucidated.Here,we review the general properties of pyrroloquinoline quinone and its capacity to modulate metabolic and mitochondrial mechanisms in physiological contexts.In addition,we analyze the neuroprotective properties of pyrroloquinoline quinone in different neurodegenerative conditions and consider future perspectives for pyrroloquinoline quinone’s potential in health and disease.
基金Supported by the Youth Foundation of Nanyang Institute of Technology and Science&Technology Research Projects of Henan Provincial Education Department(14B150035)
文摘A novel coordination polymer [Ba2（AQTC）（H2O）3]n（1, H4 AQTC = anthraquinone-1,4,5,8-tetracarboxylic acid） has been prepared under hydrothermal conditions and characterized by single-crystal X-ray diffraction, elemental analysis, infrared spectroscopy and thermogravimetric analysis. Two quinone oxygen atoms and all carboxylate oxygen atoms of AQTC4- are involved in coordination. Two equivalent barium ions are mainly linked by carboxylate oxygen atoms into a dimer. Neighbouring dimers are further connected by the AQTC4- ligand through carboxylate oxygen atom, leading to a 1-D chain structure. Every two adjacent chains are mainly further connected by face carboxylate oxygen atoms and water molecule, generating a two-dimensional layer structure. Such 2-D layer structures are connected with O（6） and O（6C） atoms from water molecules to form a 3-D structure. In addition, luminescent properties of 1 are also investigated.
基金supported by the National Key Research and Development Plan of China(2016YFD0501207)the China Agriculture Research System(CARS-36)
文摘Background: Pyrroloquinoline quinone(PQQ), which is a water soluble, thermo-stable triglyceride-quinone, is widely distributed in nature and characterized as a mammalian vitamin-like redox cofactor. The objective of this study was to investigate the effects of pyrroloquinoline quinone disodium(PQQ·Na2) on reproductive performance in sows.Results: Dietary supplementation with PQQ·Na2 significantly increased the total number of piglets born, the number of piglets born alive and the born alive litter weight. It also increased the antioxidant status in the placenta, plasma and milk. The concentration of NO was significantly increased in the plasma and placenta. RNA-seq analysis showed that462 unigenes were differentially expressed between the control(Con) treatment and PQQ treatment groups.Among these unigenes, 199 were upregulated, while 263 unigenes were downregulated. The assigned functions of the unigenes covered a broad range of GO categories. Reproduction(27, 7.03%) and the reproduction process(27, 7.03%) were assigned to the biological process category. By matching DEGs to the KEGG database, we identified 29 pathways.Conclusions: In conclusion, dietary supplementation with PQQ·Na2 in gestating and lactating sows had positive effects on their reproductive performance.
基金supported by the National Natural Science Foundation of China(Grant No.32072772,31672459,31372317 and 30871808).
文摘Background:Oxidative stress is a main cause of piglet gut damage and diarrhea.Pyrroloquinoline quinone(PQQ),is a novel redox cofactor with antioxidant properties.However,the effect and mechanism that PQQ supplementation decreases oxidative injury in weaned pigs is not understood.Therefore,the aim of this study is to confirm the effect of PQQ on regulating redox status in weaned pigs and the mechanism for antioxidant function by porcine intestinal epithelial cell line(IPEC-J2)challenged with H_(2)O_(2).Results:Experiment 1,144 Duroc×Landrace×Yorkshire pigs(weaned at 28 d)were allocated to four groups:received a basal diet(control)and diets supplemented with 0.15%,0.30%and 0.45%PQQ,respectively.On d 28,growth performance,diarrhea incidence and redox factors were measured.Experiment 2,IPEC-J2 were treated with or without PQQ in the presence or absence of H_(2)O_(2)for indicated time points.Experiment 3,IPEC-J2 were transfected with or without Nrf2 siRNA,then treated according to Experiment 2.The cell viability,redox factors,protein of tight junctions and Nrf2 pathway were determined.In vivo,PQQ supplementation demonstrated dose-related improvements in average daily gain,and gain to feed ratio(Linear P<0.05).During d 0–28,compared to controls,0.45%PQQ supplementation for pigs decreased diarrhea incidence and MDA content in liver and jejunum,and increased concentration of SOD in liver;0.3%PQQ supplementation decreased ileal and liver MDA concentration;and 0.15%PQQ supplementation decreased ileal MDA concentration(P<0.05).In vitro,compared to cells cultured with H_(2)O_(2),pre-treatment with PQQ increased cell viability,tight junction proteins expression including ZO-1,ZO-2,Occludin and Claudin-1;and decreased ROS concentration and level of Caspase-3(P<0.05);as well as upregulated the ratio of Bcl-2 to Bax and protein expression of nuclear Nrf2,HO-1.Notably,Nrf2 knockdown by transfection with Nrf2 siRNA largely abrogated the positive effects of PQQ pretreatment on H_(2)O_(2)-induced intracellular changes.Conclusions:PQQ administration attenuated oxidative stress in weaned pigs which is associated with activation of Nrf2/HO-1 pathway.
基金Project supported by the Applied Basic Research Foundation of Yunnan Province (1999C0081M). Authors would like to thank the staf
文摘Two new diterpenoid quinones, colean S and T were isolated from the chloroform extract of the leaves of Coleus forskohlii, and based on spectroscopic data, their structures were identified as 1,4-phananthrenedione-4b,5,6,8a,9,10-hexahydro-3,9 beta ,10 alpha- tri-hydroxy-4b,7,8-trimethyl-2-propylene(2), respectively.
基金the National Natural Science Foundation of China(No.81171760).
文摘Osteoarthritis(OA)is a degenerative disease characterized by matrix degradation and cell death leading to a gradual loss of articular cartilage integrity.As a bacterial synthesis of quinine,pyrroloquinoline quinone(PQQ)is a strong redox cofactor with a variety of biological benefits,including antioxidant,anti-inflammation-induced mitochondrial metabolism regulation.This study was designed to investigate the effect of PQQ on TNF-α-induced mitochondrial damage in chondrocytes.Chondrocytes isolated from C57BL/6 mice were exposed to TNF-α50 ng/mL,TNF-α50 ng/mL+PQQ 10µmol/L for 24 h.Then,morphological study,functional study and mechanism study were taken.The results revealed TNF-α-induced chondrocyte mitochondrion damage could be reduced by application of PQQ,evidenced by elevated number of mitochondria,well-kept mtDNA integrity,preserved ATP level,reestablished mitochondrial membrane potential,and prevented mitochondrial function.The present work strongly suggests that the mitochondrion is an important target for OA chondrocyte damage induced by TNF-αand the PQQ protection from this damage ameliorates mitochondrial dysfunction induced by TNF-α.PQQ might be a potential chemical for OA intervention.
基金Supported by the National Natural Science Foundation of China,No.31971188 and No.81773189the Nature Science Foundation of Zhejiang Province,China,No.LQ16H160004 and No.LY17H270002The Hygiene Department of Zhejiang,No.2016KYB139.
文摘BACKGROUND Quinine oxidoreductase 1(NQO1)plays a vital role in protecting normal cells against oxidative damage and electrophilic attack.It is highly expressed in many solid tumors,suggesting a role in cancer development and progression.However,the role of NQO1 in gastric cancer and its effect on cancer development and prognosis have not been fully investigated.AIM To investigate the clinical relevance of NQO1 protein expression in gastric cancer and to explore the potential of NQO1 to serve as a prognostic biomarker and therapeutic target.METHODS In this retrospective study,gastric cancer specimens of 175 patients who were treated between 1995 and 2011 were subjected to immunohistochemistry analyses for NQO1.The correlation of NQO1 expression with gastric cancer prognosis and clinical and pathological parameters was investigated.RESULTS NQO1 protein was overexpressed in 59.43%(104/175)of the analyzed samples.Overexpression of NQO1 was associated with a significantly inferior prognosis.In addition,multivariate analysis suggested that NQO1 overexpression,along with tumor stage and patient age,are prominent prognostic biomarkers for gastric cancer.Moreover,NQO1 overexpression was correlated to a better response to 5-fluorouracil(5-FU)-based adjuvant chemotherapy.CONCLUSION NQO1 overexpression is associated with a significantly poor prognosis and better response to 5-FU in patients with gastric cancer.These findings are relevant for improving therapeutic approaches for gastric cancer patients.
基金supported by Fujian Ubaifu Biotechnology Co.Ltd.,Fuzhou,Chinathe Special Funds of Chinese Academy of Agricultural Sciences for Distinguished Scientists+1 种基金the earmarked fund for China Agriculture Research System(CARS-41)the Agricultural Science and Technology Innovation Program(ASTIP-IAS08)。
文摘This study was conducted to investigate the effect of dietary supplementation with pyrroloquinoline quinone(PQQ) in the form of PQQ disodium(PQQ·Na2) on the growth performance, carcass traits, meat quality and antioxidative ability of broilers. A total of 720 one-d-old Arbor Acres male broilers were randomly allocated to 1 of 6 treatments with 8 replicates of 15 birds per replicate in a completely randomized design. Birds were fed a PQQ·Na2-unsupplemented corn-soybean meal basal diet(control) or the basal diet supplemented with 0.1, 0.2, 0.3, 0.4 or 0.5 mg PQQ·Na2 kg-1 for 42 d. Compared with the control chicks, the chicks fed the diets supplemented with PQQ·Na2 had lower(P<0.05) feed:gain(F/G) during the grower phase and drip losses of breast muscles on day 42. As supplemental PQQ·Na2 level increased, plasma total antioxidant capacity(T-AOC) on d 42, liver T-AOC on d 21 and heart T-AOC on d 21 and 42 increased linearly(P<0.05), but malondialdehyde concentrations in plasma, liver and heart on d 21 or 42 decreased linearly(P<0.001) or quadratically(P<0.005). The results from the present study indicate that dietary supplemental PQQ·Na2 can improve antioxidant ability and meat quality of broilers, and in general, it is implied that the optimal supplemental PQQ·Na2 level is 0.1 mg kg-1 of diet for broilers from 1 to 42 d of age.
文摘AIM： To investigate the expression and activity of NAD（P）H quinone oxidoreductase 1 （NQO1） in human liver specimens obtained from patients with liver damage due to acetaminophen （APAP） overdose or primary biliary cirrhosis （PBC）. METHODS： NQOt activity was determined in cytosol from normal, APAP and PBC liver specimens. Western blot and immunohistochemical staining were used to determine patterns of NQO1 expression using a specific antibody against NQO1. RESULTS： NQO1 protein was very low in normal human livers. In both APAP and PBC livers, there was strong induction of NQO1 protein levels on Western blot. Correspondingly, significant up-regulation of enzyme activity （16- and 22-fold, P〈0.05） was also observed in APAP and PBC livers, respectively. Immunohistochemical analysis highlighted injury-specific patterns of NQO1 staining in both APAP and PBC livers. CONCLUSION： These data demonstrate that NQO1 protein and activity are markedly induced in human livers during both APAP overdose and PBC. Up-regulation of this cytoprotective enzyme may represent an adaptive stress response to limit further disease progression by detoxifying reactive species.
基金supported by the National Key Research and Development Program of China(No.2018YFC 0310900)the National Natural Science Foundation of China(Nos.U1605221,82022068,81773866,41906075,and 41576130)。
文摘Four new sesquiterpene quinone meroterpenoids,dysideanones F—G(1—2)and dysiherbols D—E(3—4),were isolated from the marine sponge Dysidea avara collected from the South China Sea.The new structures were elucidated by extensive analysis of spectroscopic data including HR-MS and 1D and 2D NMR spectra,and their absolute configurations were assigned by single-crystal X-ray diffraction and ECD calculations.Anti-inflammatory evaluation showed that dysiherbols D—E(3—4)exhibited moderate inhibitory activity on TNF-α-induced NF-κB activation in human HEK-293T cells with IC_(50)values of 10.2 and 8.6μmol·L^(-1),respectively.
基金supported by grants from the National Natural Science Foundation of China (No.30971255)
文摘Our previous studies showed that resveratrol could inhibit the proliferation of vascular smooth muscle cells （VSMCs） and repress mRNA and protein expression of quinone reductase 2 （NQO2）. This study further explored the potential mechanisms whereby resveratrol inhibits the proliferation of rat VSMCs. Lentiviral vectors that incorporated NQO2 small interfering RNA （siRNA） were constructed and transduced into rat VSMCs. The cell proliferation was detected using the bromodeoxyuridine （BrdU） assay. Cultured rat VSMCs were stimulated with angiotensin II and the level of reactive oxygen species （ROS） was measured using a ROS assay kit. A realtime quantitative PCR was used to detect NQO2 mRNA levels. Extracellular signal-regulated kinase （ERK1/2） and NQO2 protein expression were determined by Western blotting analysis. The inhibitory effect of resveratrol （10 and 50 μmol/L） on the proliferation of rat VSMCs in the NQO2 siRNA group was significantly weaker than that in the normal and scrambled siRNA group （P 〈 0.01）. The ROS level in the NQO2 siRNA and resveratrol （50 μmol/L） treatment groups were lower than that in the normal and scrambled siRNA groups （P 〈 0.01 in both）. Compared with the normal and scrambled siRNA group, the phosphorylation of ERK1/2 was significantly decreased in the NQO2 siRNA and resveratrol （50 μmol/L） treatment group （P 〈 0.01 in both）. In conclusion, high concentration of resveratrol inhibits angiotensin II-induced ERK1/2 phosphorylation and subsequent proliferation by down-regulation of NQO2 in cultured rat VSMCs.
基金Supported by the Third World Academy of Science(TWAS)Fellowship for Research and Advanced Training FR number:Grant No.3240224121the International Foundation for Science dFS,Stockholm.Swedem and the Organization for the Prohibition of Chemical Weapons(OPCW)dFS Research Grant No.F/4921-2)
文摘Objective:To validate scientifically the traditional use of Salacia leptoclada Tul.(Celastraceae)(S.leptoclada)and to isolate and elucidate the structure of the biologically active compound.Methods:Bioassay-guided fractionation of the acetonic extract of the stem barks of S.leptoclada was carried out by a combination of chromatography technique and biological experiments in viro using Plasmodium falciparum and P388 leukemia cell lines as models.The structure of the biologically active pure compound was elucidated by 1D and 2D NMR spectroscopy and mass spectrometry.Results:Biological screening of S.leptoclada extracts resulted in the isolation of a pentacyclic triterpenic quinone methide.The pure compound exhibited both in vitro a cytotoxic effect on murine P388 leukemia cells with IC_(50)value of(0.041±0.020)μg/mL and an antiplasmodial activity against the chloroquine-resistant strain FC29 of Plasmodium falciparum with an IC_(50)value of(0.052±0.030)μg/mL.Despite this interesting anti-malarial property of the lead compound,the therapeutic index was weak(0.788).In the best of our knowledge,the quinone methide pentacyclic triterpenoid derivative compound is reported for the first time in S.leptoclada.Conclusions:The results suggest that furthers studies involving antineoplastic activity is needed for the development of this lead compound as anticancer drug.
文摘The structures of two new abietane quinones, named micranthins A and B, were determined to be 7a-methoxy-14, 16-epoxy-8, 13-abietadiene-11, 12-dione (1) and 16-acetoxy-6, 7-dehydroroyleanone (2) respectively, which were isolated from Isodon lophanthoides var. micranthus.
基金Financial support from the National Natural Science Foundation of China (No: 29975002) is gratefully acknowledged.
文摘CIDNP techniques were applied to study the mechanism of photocycloadditions of 2-chloro-5-methoxybenzoquinone 1 with arylacetylenes 2-5 in benzene-d6 and acetonitrile-d6 respectively.
文摘Photocatalytic splitting of water was carried out in a two-phase system. Nanocrystalline titanium dioxide was used as photocatalyst and potassium hexacyanoferrate(III)/(II) as electron transporter. Generated hydrogen was chemically stored by use of a 1,4-benzoquinone/1,4-hydroquinone system, which was used as a recyclable fuel in a commercialised direct methanol fuel cell (DMFC). The electrical output of the cell was about half compared to methanol. The conversion process for water splitting and recombination in a fuel cell was monitored by UV-Vis spectroscopy and compared to a simulated spectrum. Products of side reactions, which lead to a decrease of the overall efficiency, were identified based on UV-Vis investigations. A proof of principle for the use of quinoide systems as a recyclable hydrogen storage system in a photocatalytic water splitting and fuel cell cyclic process was given.
文摘Resveratrol is a dietary polyphenol espoused to have chemopreventive activity against a variety of human cancer types. We first reported that resveratrol significantly decreases the proliferation of both androgen-dependent and hormone-refractory prostate cancer cells. However, the effects of resveratrol in normal prostate epithelial and stromal cells, particularly with regard to its uptake, subcellular distribution and intracellular targets, have not been investigated. To advance the knowledge on accessibility and cellular disposition of resveratrol in prostate cells, [3H] resveratrol, fractionation of cell extracts into subcellular compartments, Western blot analysis, resveratrol affinity column chromatography and flow cytometry were used to study the uptake and intracellular distribution of resveratrol in normally cultured prostate stromal （PrSCs） and epithelial cells （PrECs）. Pretreatment of both PrSCs and PrECs for 2 days with resveratrol modulated its uptake and selectively increased its distribution to the membrane and organelle compartments. Resveratrol affinity column chromatography studies showed differential expression of a previously identified resveratrol-targeting protein, quinone reductase 2 （QR2）, in PrSCs and PrECs. Flow cytometric analysis comparing resveratrol-treated and untreated PrSCs showed a large decrease in G1-phase and a concomitant increase in S and G2/M-phases of the cell cycle. These results suggest that resveratrol suppresses PrSC proliferation by affecting cell cycle phase distribution, which may involve the participation by QR2.
文摘Emodin and shikonin are quinones that are commonly found in the roots of plant species of the families Polygonaceae and Boraginceae,respectively.They have a wide spectrum of bioactivities,including anti-cancer properties.This overview on the cytotoxic properties of emodin and shikonin is focused on lung cancer,the leading cause of cancer death in the world.In emodin,the-OH groups at C1 and C3 positions,while in shikonin,the-OH groups of the naphthazarin moiety and chiral side-chain,are important for their anti-tumour functions.Studies have shown that emodin and shikonin inhibit the growth of lung cancer cells by inducing apoptosis,autophagy,necrosis and early senescence,and by inhibiting proliferation,invasion,migration and metastasis.The cytotoxic activities are involved multiple molecular targets and signalling pathways.A clinical trial using shikonin to treat patients with late-stage lung cancer has been presented.Some future perspectives and research needs are suggested.Sources of information are from Google Scholar,Pub Med,Science Direct,J-Stage,Pub Chem and CNKI.
基金financially supported by the National Natural Science Foundation of China (No. 21801139)the Natural Science Foundation of Jiangsu Province (Nos. BK20180942, BK20190917)+1 种基金the Natural Science Foundation of the Higher Education Institutions of Jiangsu Province (No. 19KJB150015)the Six Talent Peak Projects in Jiangsu Province (No. XCL-085)。
文摘Water-soluble pillar[5]arenes are a class of typical macrocycles and have aroused tremendous attention for its easy to modify, abundant host-vip properties and extensive applications. However, up to now, all the reported water-soluble pillar[5]arenes acted as the host molecules, whereas they failed to be postsynthetically modified, which seriously impeded the development of the pillar[5]arene-based supramolecular chemistry. In this work, a new water-soluble pillar[5]arene, pillar[4]arene[1]quinone, was designed and synthsized with eight quaternary ammonium groups as well as a quinone units. Such a new water-soluble pillar[4]arene[1]quinone was capable of forming 1:1 stable complex with sodium 1-octanesulfonate in aqueous solution. Since the 1,4-quinone unit of WP[4]Q[1] could react with ethylenediamine (EDA) to form a conjugated quinoxaline structure, so pillar[4]arene[1]quinone could apply to the facile fluorescence turn-on sensing of EDA in aqueous solution, organic solvent and air.
